hal: Add open source HAL for Elliptic Ultrasound

Author: Balázs Triszka <balika011@gmail.com>
Date:   Thu May 11 03:19:29 2017 +0200

    msm8998: ultrasound: Initial open source hal for Elliptic Ultrasound

    * Needed for proximity sensor on Xiaomi Mi MIX

    [Arasthel]: Change PCM id for Mi MIX 2 implementation

    Change-Id: Iaef2266bc1b853d7a9d1e2a906014c6c91019d5f
    Signed-off-by: Balázs Triszka <balika011@gmail.com>

Author: Michael Bestas <mkbestas@lineageos.org>
Date:   Sat Feb 10 00:28:00 2018 +0200

    msm8998: ultrasound: Remove unused code

     * Params ultrasound_set_manual_calibration and ultrasound_set_sensitivity
       do not exist.

    Change-Id: I0004949db19b6ab7d49f20e422984e06a970cfe9

Author: Demon Singur <demonsingur@gmail.com>
Date:   Sat Apr 21 09:08:03 2018 +0000

    msm8998: hal: Update ultrasound route hacks

    Change-Id: If002503dfba0f005f73a4455d68bbcce9d2f617e

Change-Id: I119316f264afbda9faf24950edfbca3891aa9769

Author: Vol Zhdanov <wight554@gmail.com>
Date:   Fri Feb 1 02:16:26 2019 +0000

    hal: fix channels swap for elliptic ultrasound devices

    Change-Id: Id45b075c4ad098c95fcb617da10c56d38565b9c8

Change-Id: Icb18f5b41483d33188be103e13b6c915b6e681b8
diff --git a/hal/Android.mk b/hal/Android.mk
index 5fb3322..d5aa190 100644
--- a/hal/Android.mk
+++ b/hal/Android.mk
@@ -336,6 +336,11 @@
     LOCAL_SHARED_LIBRARIES += vendor.qti.hardware.audiohalext@1.0
 endif
 
+ifeq ($(strip $(AUDIO_FEATURE_ELLIPTIC_ULTRASOUND_SUPPORT)),true)
+    LOCAL_CFLAGS += -DELLIPTIC_ULTRASOUND_ENABLED
+    LOCAL_SRC_FILES += audio_extn/ultrasound.c
+endif
+
 LOCAL_CFLAGS += -D_GNU_SOURCE
 LOCAL_CFLAGS += -Wall -Werror